DCIS is known as stage zero or non-invasive breast cancer, meaning the cancer has not broken through the lining of the milk ducts, explains Kathie-Ann Joseph, MD, Director Breast Services at the Health and Hospitals Corporation, NYU Medical Center in New York. It makes up about 25 percent of all breast cancers. “If you are going to get breast cancer, this is the one to get,” Joseph says, citing its 99 percent survival rate and the unlikelihood that chemotherapy will be required.